Large file into an array

[Filik]

Hi,
I have a large file, which i need to read into an array.
As i understand, i have to use an arrayList, but my code doesnt work. Surely there's a minor error there somewhere, cause i never used arrays much, and dont know much about their use. Anyway, here's my code:

Dim a As Integer = 0
        Dim List As ArrayList  
Dim ls As New StreamReader(Application.StartupPath & "/Largefile.txt")
        Dim listing As String()
        listing = ls.ReadToEnd.Split(vbNewLine)
        For Each item As String In listing
            List.Add(item)
            a += 1
        Next

The error is "object reference is not set to an instance of an object", its here: " List.Add(item)"

Thx